A process for hot filling a container with a sterilized liquid, generally
at a temperature that is between 60 to 95.degree. C. An embodiment of the
process includes (a) providing a container that is made of a polymer and
following a process that can make it able to withstand the hot filling of
said liquid; (b) filling the container with said hot liquid; (c) closing
the filled container immediately after filling; (d) allowing the
container to cool at least below a transition temperature that is on the
order of from 40.degree. C. to 50.degree. C. and forming a depression
inside the container, resulting in visible deformation; and (e) heating
the container to bring about a relief of the residual stresses, whereby
this relief leads to a shrinkage and consecutively generates an internal
pressurization that compensates for at least the deformation undergone by
the effects of the depression of stage (d).